A significant amount of carbon dioxide is used in enhanced oil recovery (“EOR”). An oil well typically collects approximately 30 percent of its oil from an underground oil reservoir during the primary recovery phase. An additional 20 percent of the oil may be recovered using secondary recovery techniques, such as water flooding that raises the underground pressure. The EOR process provides a tertiary recovery technique capable of recovering an additional 20 percent or more of the oil from the underground reservoir.
During the EOR process, large quantities of carbon dioxide are injected into the underground oil reservoir, thereby urging additional oil from the well. Carbon dioxide is a preferred EOR gas due to its ability to mix with the underground oil and render the oil less viscous and more readily extractable.
The carbon dioxide used in EOR processes may be obtained from various sources using various techniques. For example, carbon dioxide may be collected from natural sources, such as ambient air, or may be collected as a byproduct of various industrial purposes, such as beer fermentation. Unfortunately, traditional carbon dioxide production techniques are energy intensive, particularly when run on an industrial scale. Furthermore, the cost of transporting carbon dioxide from the production site to the EOR site (e.g., by freight or pipeline) is quite significant.
Accordingly, those skilled in the art continue with research and development efforts in the field of carbon dioxide production and delivery.